Inferior alveolar nerve block failure

I have 100% failure in making inferior alveolar nerve block. Patient feels numbness in lower lip, tongue, gingiva, jaw, but never in tooth. I can ' t even make a filling because of constant pain of the tooth. I ve watched several videos, techniques, but none of them work. It frustrates, and makes me unable to work. It s becoming a trust issue for patients. How is it possible? What should I do?